Treatment Outcomes in Acute Promyelocytic Leukemia Patients Using a Uniform ATRA + ATO Consolidation Therapy Regimen across All Risk Groups: A Single Centre Study from India

• Published in: Blood 2024-11, Vol.144, p.1491-1491
• Main Authors: Benson, Reshma, Kachhwaha, Arjun, Satadeve, Paras, Gupta, Adamya, Kumar, Karthik, Singh, Sashi, Nayak, Jhasaketan, Ronanki, Kavya, Dalton, Prisla, Shah, Bibhant, Nagpal, Nikhil, Nath, Uttam Kumar
• Format: Article
• Language: English
• ISSN: 0006-4971
• DOI: 10.1182/blood-2024-210206

INTRODUCTION Acute Promyelocytic Leukemia (APL) is a particularly aggressive subtype of acute myeloid leukemia associated with high risk of early mortality due to coagulopathy & bleeding. The current standard induction therapy for APL comprises of all-trans retinoic acid (ATRA) plus arsenic trioxide (ATO), with or without anthracyclines. However, the consolidation regimens recommended for APL are highly variable according to risk group & cardiac function, and include different combinations of ATRA, ATO, anthracyclines, cytarabine, &/or gemtuzumab ozogamicin. Anthracyclines have been historically included in consolidation regimens, particularly in high-risk (HR) patients. Herein, we present the treatment outcomes with a uniform ATRA+ATO consolidation regimen in both low-risk(LR) & HR APL patients. To study the clinical outcomes in APL patients treated with uniform ATRA+ ATO consolidation regimen across all risk groups. Data of all APL patients who were treated between October 2021 & July 2024 was retrospectively analysed. Induction therapy consisted of ATRA at 45mg/m2 plus injection ATO at 0.15mg/kg daily, till documentation of morphological complete remission (CR). HR patients received 1-2 doses of Daunorubicin at 60mg/m2 dose. All the patients, irrespective of their baseline risk stratification, received uniform consolidation therapy comprising of ATRA+ATO. Injection ATO was administered at dose of 0.15 mg/kg/day by intravenous infusion, for 5 days/week for 4 weeks, every 8 weeks for a total of 4 cycles. ATRA was administered at dose of 45 mg/m2/day for 2 weeks every 4 weeks, for a total of 7 cycles. Patients below 18 years of age received ATRA at 25 mg/m2/day dose. Bone marrow PCR for PML-RARA for assessment of molecular remission was done after the 3rd cycle of consolidation. None of the patients who completed consolidation therapy received any maintenance therapy. All patients in HR group received four doses of intrathecal cytarabine in consolidation phase for CNS prophylaxis. Total 39 patients were diagnosed with APL (LR 54%, HR 46%) and were started on induction therapy. The median age was 30 years (range 9-72) and male: female ratio was 1.2:1. The median total leukocyte count & platelet count at presentation were 3.6x109/L (range 0.29-176) and 17x109/L (range 2-48) respectively. Sixty percent of patients had disseminated intravascular coagulation (DIC) & 20% had intracranial bleed at the time of presentation. Approximately 32% patients developed dif